1. Field of the Invention
The invention relates to an apparatus for agitating media which are arranged on a shelf, comprising a housing with an agitating mechanism, which can be used to cause the shelf to make agitating movements, and with at least one sensor connected to a control unit which has sensor electronics.
2. Description of the Related Art
As far as media which are to be examined in the laboratory, for example for biological fermentation processes, and need to be kept in motion, this is done using laboratory shakers. The laboratory shakers have an essentially horizontal shelf which holds the medium to be examined, for example in an agitating flask. In this case, the shelf is caused to make a circular movement, a longitudinal movement or a tilting movement by an agitating mechanism arranged in a housing. In order to examine the medium kept in motion, sensors are used. In addition, with the increasing need to equip each agitating flask on a shelf with sensors or with a sensor system for variables such as oxygen content or pH value, in order just to collect data for the process development in this case, the shelf currently needs to accommodate ever more sensors with the associated wiring arrangements, sensor electronics and data lines.
One of the main problems for the indication of sensor systems on a laboratory agitator is the fact that the media to be examined need to be in motion, which means that it is necessary to transmit sensor signals from the sensors to the sensor electronics or to a control unit via permanently moving, kinked cables, which, particularly in the case of numerous measuring lines, presents an electromechanical problem as a result of possible cable fracture.
WO 02/101000 A2 discloses an agitating machine for biological fermentation. In the case of the known agitator, the sensors or measuring heads are arranged separately from the shelf, so that the shelf moves relative to the measuring heads. However, this is possible only using contactless, optical measuring methods and rules out arranging sensors on the shelf or on or in an agitating flask.
It is therefore an object of the present invention to specify an apparatus for agitating media, to monitor the one measurement-based monitoring of the media kept in motion, which are arranged on a shelf, particularly in agitating flasks, using sensors arranged on the shelf, and in so doing to avoid mechanical problems, such as cable fracture in measuring lines for processing measured values.
This object is achieved by virtue of the at least one sensor and the sensor electronics connected to the sensor being arranged on the shelf and communicating wirelessly with the fixed control unit.